Obstruction Device for Flowing Waterways

ABSTRACT

The invention concerns an obstruction device for flowing waterways and rivulets of all kinds, in particular for torrents and similar river beds, with a flexible barrier element in the form of a catchment net ( 4 ), extending from one riverbank ( 2 ) to the other riverbank ( 3 ) transverse to the flow direction ( 7 ). The catchment net ( 4 ) is installed between a lower support rope ( 5 ) and an upper support rope ( 6 ). The support ropes ( 5, 6 ) are anchored in the riverbanks ( 2, 3 ) with rope anchors ( 8, 9 ) attached to their ends, whereby the rope anchors ( 9 ) of the upper support rope ( 6 ) are offset to the front relative to the rope anchors ( 8 ) of the lower support rope ( 5 ) in flow direction ( 7 ). In this way the catchment net ( 4 ) can deform itself when the barrier is filled in such a way that the water, rocks, flotsam etc. then overflowing the net will contact the same either not at all, or only briefly. In this way it is safely and permanently protected against the corrosion and abrasion effect of the overflowing water.

The invention concerns an obstruction device for flowing waterways and rivulets of all kinds, in particular for torrents and similar river beds, with a flexible barrier element for rocks, flotsam and drifting objects, that can be erected between riverbanks transverse to the flow direction.

An obstruction device of this type is described in the German patent application DE 203 00 821. It is known that devices of this type reduce the energy of the flowing water to serve as a protection against the destructive effects of a flooded torrent, and therefore inhibit riverbank erosion as well as the transport of rocks, flotsam, and drifting objects. The known obstruction device with its catchment net serving as a barrier element forms a flexible blocking system with a large energy absorption capacity, which also remains undamaged when the device is overflowed.

However, if one leaves a filled barrier without emptying the same the continuous water flow across the catchment net and the support ropes serving as holding and tensioning elements will erode the surface protection of these parts, which will result in the destruction of the barrier in the long term due to corrosion and abrasion of the most important elements of the same. In order to prevent a corrosion of the support ropes it is known to use corrosion protection wires made of steel, which are also coated. The catchment net itself remains substantially unprotected against the abrasion and corrosion effect of the continuous water flow.

It is the purpose of the invention to prevent this disadvantage, and to provide an obstruction device of the type described above, the barrier element of which will be protected against long-term corrosion and abrasion effects applied by the overflowing water when the barrier is filled.

This task is solved in accordance with the invention in that the flexible barrier element is deformed in such a way when the barrier is filled that material will overflow the barrier element in a downstream direction only a little when the barrier is filled. In this way it is ensured that the water, fine material, blocks and suchlike overflowing the barrier element in a downstream direction will contact the barrier only briefly, or not at all. In this way the same is safely and permanently protected against corrosion and abrasion effects applied by the overflowing water.

The invention further concerns an obstruction device with a catchment net forming the barrier element installed between a lower and an upper support rope as well as optional interim ropes extending transverse to the flow direction, whereby the support ropes are anchored at the riverbanks with rope anchors or other anchor types attached to their ends.

In order to solve the task of the invention it is envisaged that the rope anchor or the other anchor types of the upper support rope are offset towards the front in flow direction relative to the rope anchors or other anchor types of the lower support rope. In this way the catchment net is given the necessary installation position to enable the same to deform following a subsequent filling of the barrier in such a way that material flowing across the catchment net in a downstream direction will contact the same only briefly, or not at all.

Depending on the degree of flexibility of the catchment net and the operating conditions for the barrier on site it will make sense to offset the rope anchor of the upper support rope so far towards the front relative to the rope anchor of the lower support rope that the non-deformed, level upper catchment net is inclined towards the front at an angle of preferably 10° to 45° in flow direction.

The invention also concerns a further obstruction device of the type described above, the barrier element of which forming the catchment net comprises a middle zone and two riverbank zones projecting further than the same in the direction of the riverside, and installed between a lower and an upper support rope and optionally tensioned with interim ropes transverse to the flow direction, whereby the support ropes are guided by means of two supports delimiting the middle zone in a widthways direction. These supports are preferably jointably affixed and anchored in a backward direction with retaining ropes.

In order to solve the task of the invention it is suggested in this case to position the supports in such a way that the same are inclined in a forward direction relative to the vertical in flow direction. In this way the catchment net is equipped with the necessary installation position in its middle zone to enable the same to deform in this zone when the barrier is filled in such a way that material overflowing in a downstream direction will not contact the same. In this way the catchment net can be protected in that area of the net in a targeted way in which the same would be subject to the highest flow speeds, and therefore the strongest abrasion effects applied by water and rocks when the barrier is overflowed.

According to the degree of flexibility of the net and the operating conditions for the barrier it will make sense here to install the supports at an angle of inclination of preferably 10° to 30° from the vertical.

In order to optimise the permanent protection of the system elements in the upper area of the barrier the invention envisages that an overflow protection can be installed across the upper edge area of the catchment net. The overflow protection has the task of guiding the overflowing material over the barrier in such a way that this material will not contact the catchment net on the downstream side.

According to the invention the overflow protection can be formed by a flattened sheet metal profile or a protective metal sheet attached to the upper support rope, which is preferably fitted to the upper edge of the catchment net when the barrier is full.

Further preferred embodiments of the device of the invention form the subject of the Claims 8 to 10.

The invention will now be described in more detail with reference to the drawings, whereby:

FIG. 1 shows a front view of an obstruction device of the invention;

FIG. 2 shows a schematically illustrated cross-section through the device illustrated in FIG. 1 prior to filling the barrier;

FIG. 3 shows the schematic cross-section illustrated in FIG. 2 when the barrier is filled;

FIG. 4 shows a schematic cross-section through an obstruction device according to prior art prior to filling the barrier;

FIG. 5 shows the cross-section illustrated in FIG. 4 when the barrier is filled;

FIG. 6 shows a front view of a further obstruction device according to the invention;

FIG. 7 shows a cross-section through the device illustrated in FIG. 6 prior to filling the barrier;

FIG. 8 shows the cross-section illustrated in FIG. 7 when the barrier is filled; and

FIG. 9 shows the cross-section illustrated in FIG. 3 with the overflow protection for the upper edge area of the barrier.

The obstruction device shown in FIGS. 1 to 3 is positioned in a river or rivulet with a river bed floor 1 and two riverbanks 2, 3. It comprises a flexible barrier element for rocks, flotsam, and drifting objects in the form of a catchment net 4, which extends from the riverbank 2 to the riverbank 3, and between a lower support rope 5 and an upper support rope 6 extending transverse to the flow direction 7. The support ropes 5 and 6 are anchored in the riverbanks 2, 3 with rope anchors 8, e.g. 9 affixed to their ends, whereby the rope anchor 9 of the upper support rope 6 is offset to the front in relation to the rope anchors 8 of the lower support rope 5 in flow direction 7.

The catchment net 4 is formed as a flexible ring or spiral rope net, which is almost level in its installed condition prior to filling the barrier, and which deforms into an arched shape in flow direction when the barrier is filled due to its flexibility. These two conditions are schematically illustrated in FIG. 2, e.g. 3.

In the installation position shown in FIG. 2 the level of the catchment net is inclined forward in flow direction 7 at an angle 10, whereby the incline results from the pre-installation of the rope anchors 9 relative to the rope anchors 8. The angle 10 is selected in such a way that the catchment net 4 is deformed when the barrier is filled, so that material then overflowing the catchment net 4 in a downstream direction will contact the same only briefly, or not at all, as is clear from FIG. 3. The angle 10 is preferably between 10° and 30° (or even 40°) depending on the consistency of the catchment net and the operating conditions for the barrier.

The pre-installation of the rope anchors 9 relative to the rope anchors 8 is a simple process, which requires no additional constructive and construction technical effort in addition to those required for known barriers. As is clear from FIG. 4 the catchment net 4 associated with these is tensioned vertically in its installation position by means of the support ropes prior to the barrier being filled. In this way the catchment net deforms when the barrier is filled in such a way that the material then overflowing the said catchment net 4 in a downstream direction will not contact the same, as is shown in FIG. 5. In the long term this will prevent damage to the catchment net through the corrosion and abrasion effect applied by the material overflowing the same.

With the obstruction device of the invention however one can effectively protect the catchment net against corrosion and abrasion with simple means for the long term, namely by pre-installing the upper rope anchors relative to the lower rope anchors. In this way the system will remain safe and operational for longer.

The measure of the invention can easily be retrofitted to existing barriers as well.

For improved protection of the system elements in the upper area of the barrier an overflow protection in the form of a flattened sheet metal profile 11 is envisaged, which—as can be seen in FIG. 9—is fitted across the upper edge area 12 of the catchment net 4. The overflow protection ensures that the overflowing material will not contact the catchment net 4 on the downstream side when the barrier is filled. The overflow protection is preferably fitted to the upper edge of the catchment net when the barrier is full, so that the upper support rope 9 is also protected.

The obstruction device illustrated in FIGS. 6 to 8 differs from the obstruction device shown in FIGS. 1 to 3 substantially only in that its catchment net 4 is divided into a middle zone 13 and two riverbank zones 14, 15 projecting over the former in the direction of the riverbank. The catchment net 4′ is installed between a lower support rope 5′ and two upper support ropes 6′, 6″. The support ropes are anchored in the riverbanks 2′, 3′ by means of rope anchors 8′, e.g. 9′, 9″ attached to its ends.

The upper support ropes 6′, 6″ are combined horizontally with a double rope unit consisting of two supports 16, 17 in the middle zone 13 of the catchment net 4′, which define the width of the middle zone 13. The support ropes 5′, 6′, 6″ are equipped with braking elements 18 for absorbing dynamic energy, which enables a rope extension when loads are great.

As it clear from FIG. 7 the supports 16, 17 are arranged in such a way that the same are inclined forward in flow direction 7′ relative to the vertical. In this way the angle of incline 10′ is selected in such a way that the catchment net 4′ is deformed in the middle zone 13 when the barrier is filled, so that—as is clear from FIG. 8—the overflowing material will contact the catchment net 4′ in this zone only briefly. In this way the catchment net 4′ can be protected in a targeted way in the area of the net, which is exposed to the strongest abrasion effect when the barrier is filled. Depending on the degree of flexibility of the catchment net and the operating conditions of the system the angle of incline 10′ is preferably between 10° and 20°.

The measure of the invention of equipping the supports with an incline relative to the vertical can also be retrofitted to existing systems without problem.

With the two obstruction devices described here the catchment net 4, e.g. 4′ takes the form of a ring or spiral net. In the context of the invention it is however also of course possible to use other flexible barriers such as omega and rope nets.

Within the context of the invention it is also possible to equip the parts particularly at risk from abrasion on the upper net edge, in particular the support ropes 6, 6′, with abrasion protection parts in the form of protective pipes or profiles made of steel, iron or plastic. When using metal protective pipes or profiles these can preferably be equipped with galvanising or a special abrasion protection lacquer. The protective pipes are easy to replace, and therefore suitable for retrofitting. They can also be reinforced by means of additional protective pipes or suchlike. 

1. Obstruction device for flowing waterways and rivulets of all kinds, in particular for torrents and similar river beds, with a flexible barrier element (4) for rocks, flotsam and drifting objects, that can be erected between the riverbanks (2, 3) transverse to the flow direction, characterised in that the flexible barrier element (4) deforms in such a way when the barrier is filled that the material overflowing the filled barrier will contact the barrier element not at all, or only briefly on the downstream side.
 2. Obstruction device according to claim 1 with a catchment net (4) forming the barrier element installed between one or more lower, and one or more upper support ropes (5, e.g. 6) transverse to the flow direction (7), whereby the support rope(s) (5, 6) are anchored in the riverbanks (2, 3) with rope anchors or other rope anchoring means (8, e.g. 9) affixed to their ends, characterised in that the rope anchors (9) of the upper support rope(s) (6) are offset to the front relative to the rope anchors or other rope anchoring means (8) of the lower support rope(s) (5) in flow direction (7).
 3. Obstruction device according to claim 2, characterised in that the rope anchors or other rope anchoring means (9) of the upper support rope(s) (6) are offset so far to the front relative to the rope anchors or other rope anchoring means (8) of the lower support ropes (5) that the non-deformed level catchment net (4) is inclined at an angle (10) of preferably 10° to 45° towards the front in flow direction.
 4. Obstruction device according to claim 1 with a catchment net (4′) forming the barrier element, comprising a middle zone (13) and two riverbank zones (14, 15) projecting over the same in the direction of the riverbank, installed between a lower and an upper support rope (5′, e.g. 6′), and possibly equipped with interim ropes extending transverse to the flow direction (7), whereby the support ropes (5′, 6′) are guided by two supports (16, 17) delimiting the width of the middle zone (13), characterised in that the supports (16, 17) are inclined forwards in flow direction (7) relative to the vertical.
 5. Obstruction device according to claim 4, characterised in that the supports (16, 17) comprise an angle of incline (10′) of preferably 10° to 30°.
 6. Obstruction device according to claim 2, characterised in that an overflow protection (11) can be fitted to the upper edge area of the catchment net (4), which prevents rocks overflowing the catchment net from contacting the same on the downstream side.
 7. Obstruction device according to claim 6, characterised in that the overflow protection is formed by a flattened sheet metal profile (11) fitted to the upper edge area of the catchment net (4), or by a protective metal sheet attached to the upper support rope.
 8. Obstruction device according to claim 2, characterised in that device elements at risk from abrasion in the upper edge area of the catchment net (4), and in particular the upper support rope (6) are preferably associated with abrasion protection parts equipped with a special abrasion protection lacquer.
 9. Obstruction device according to claim 8, characterised in that the abrasion protection parts take the form of replaceable protective pipes or protective profiles.
 10. Obstruction device according to claim 8, characterised in that the abrasion protection parts can be retrofitted, and also reinforced. 